The invention relates to a sewing machine and more particularly relates to a cyclic pattern stitching device of a sewing machine which is automatically stopped with the needle detained at a predetermined position after at least one pattern is stitched up at least in one-cycle rotation of a selected pattern cam.
In the conventional pattern stitching sewing machine employing pattern cams rotated at a reduced speed by the drive shaft of the sewing machine, the initial stitch of a pattern is produced at random in dependence upon the angular position of a pattern cam at which the cam is stopped when the sewing machine is standstill, and it is almost impossible to expect that the selected pattern is produced from the initial starting point of the pattern cam. This is inconvenient in case the same patterns or different patterns are produced in sequence. In case of stitching such a combination of patterns, it is desirable that the sewing machine is started from the initial stitch coordinate of the pattern determined by the pattern cam and automatically stops at the last stitch coordinate of the pattern determined by the pattern cam for the purpose of stitching the next pattern from the initial stitch coordinate thereof. With the conventional pattern stitching sewing machine, it is very difficult and almost impossible to do such a pattern stitching operation only by manipulating the machine controller stopping and starting the sewing machine at a desired stitch coordinates of the pattern. In order to solve such a problem, the same assignee filed a Japanese utility model application No. 106 126/79 (U.S. patent application Ser. No. 175 203 by HISATAKE, KASUGA and SANO) disclosing the art to automatically stop the sewing machine with the needle stopped at a predetermined position after a single pattern has been formed up in one-cycle rotation of a selected pattern cam, but not after a plurality of patterns have been sequentially formed up.